Glug, glug, glug in the Aleutians

[Kull]

ORIGINAL: skrewball

I am trying to find more numbers on actual IJN SS attacks...but here is a sobering note taken from www.combinedfleet.com

"Japan started the war with 63 ocean-going submarines (i.e., not including midgets), and completed 111 during the war, for a total of 174. However, three-quarters of these (128 boats) were lost during the conflict, a proportion of loss similar that experienced by Germany's U-Boats. Most of the surviving boats were either dedicated to training roles or were recently completed and never saw combat. Of those which saw significant combat, the toll was very grim indeed. For example, of the 30 submarines that supported the Pearl Harbor attack, none survived the war.

Compared to German submarines, Japan's huge boats were relatively easy to sight visually and with radar, slow to dive, hard to maneuver underwater, easy to track on sonar, and easy to hit. Japanese hulls were also not as strong as those of German boats, and therefore could not dive as deeply nor survive such rough treatment. Also, they lacked radar until the first sets were installed in June 1944, and never had sets as good as the Allies possessed."

So it looks like a JFB should us his subs for the occasional deep strike as opposed to dedicated commerce raiding.

No question - the overall war stats paint a pretty grim picture. Accordingly, while 88% effectivity of ASW sounds horrendous, it just might be correct - especially in mid-43 (and later).

[Kull]

ORIGINAL: krupp_88mm

I am trying to find more numbers on actual IJN SS attacks

i think the most inaccurate part of this simulation may be the fact that the subs even attempt to engage these forces.. no German sub captain in their right mind would attack two transports guarded by three destroyers.. it just isn't worth it(the more transports the escorts have to guard the less effective each of them become(i wonder if this is modeled in the game)).. so i guess the question is if you tell a Japanese sub captain to 'attack convoy forces' should they wait for an easy target or throw themselves to their death at the first heavily guarded force that shows up?

I suspect you may be right, and the relatively small number of IJN sub attacks could very well be due to the high number of escorts in every Allied TF. Unfortunately almost every convoy was guarded by 3 or 4 escorts, so there's not enough variation to establish the correlation. Running a Death Box Patrol in a scenario modded to remove half or 2/3 of the Allied escorts would clarify matters. If someone were willing to make the modification, I'd run the test.

As for "ordering sub captains" to attack (or not), that's not a command one can give. You can order the submarine to patrol in harm's way, but whether it attacks or not seems kind of random. However. I had "react" set to "1". Changing that to "6" might possibly change the attack ratio (versus the "sit here submissively and be depth charged into oblivion" tactic). Another possible tweak for future tests.